Here you go.
Rest of the 0650 pics are
here.
The 0500 seems to feel a bit heavier, but the only specs I've found indicate that the 0650st is heavier.
The 0500 is a tiny bit thicker overall.
0500 = 0.73 inches at the widest part of the G-10 and about 0.81 at the lock release.
0650st = 0.67 inches at the widest part of the G-10 and about 0.72 at the release.
The MUDD's blade is also thicker.
0500 = 0.156 inches
0650st = 0.125 inches
I do have to say that the 0650st has been great so far.
The Crossfire lock has been effortless to use and has given me no problems, no misfires, and no accidental openings.
To be honest, it is pretty full of pocket lint right now, and there seems to be no effect on function.
It's funny, closing the MUDD after getting used to closing the 0650 is kind of scary. You tend to slam it closed since there is zero resistance to closing.